How do I use the Firefox spell checker?

Firefox automatically checks the spelling of words that you enter in text boxes containing more than one line. As soon as you finish typing a word, it is checked against the words in the installed dictionary. If the word is not found in the dictionary, it will be underlined in red, as in the following example:

  • Automatic spell-checking is only turned on for text boxes containing more than one line, where you can enter as much text as you want.
  • Not all locales come with a dictionary installed due to licensing reasons.

Disabling automatic spell-checking

By default, Firefox is configured to automatically check spelling. You can turn it off in the OptionsPreferences window:

  1. Click the menu button New Fx Menu and choose Options.Preferences.
  2. Select the Advanced panel.
  3. Click the General tab.
  4. Uncheck Check my spelling as I type.
    Spell Checker - Win1 Spell Checker Pref 38
  5. Close the about:preferences page. Any changes you've made will automatically be saved.
Note: Some options may not appear in the preferences window in custom builds of Firefox.

Correcting misspelled words

When spell-checking is enabled, you can easily correct misspelled words. To correct the misspelled word, Right-clickHold down the Ctrl key while you click on it and select one of the suggested words at the top of the menu.


If none of the suggested words is appropriate, you must manually edit it. If you are sure the word is spelled correctly, you can add it to the dictionary. To add a word to the dictionary, Right-clickHold down the Ctrl key while you click on it, and select Add to Dictionary.

Note: Added words apply to all your dictionaries.

Adding dictionaries

You can install other dictionaries as necessary.

  1. Right-clickHold down the Ctrl key while you click in any text box containing more than one line.
  2. Select Languages.
  3. Select Add dictionaries....
  4. The Dictionaries & Language Packs is displayed. Find a language on the list and click the "Install Dictionary" link next to it.
  5. Click the Add to Firefox button on the page that opens. When the Software Installation window appears, click Install Now to allow the installation.When the warning panel appears, click Install to allow the installation.
    Spell Checker - Win4 Spell Checker Install 40
  6. Click the Restart Now button if prompted.

Switching dictionaries

After the dictionary is installed, you can switch to it, as needed. To switch to a different installed dictionary, Right-clickHold down the Ctrl key while you click in a multi-line field, select Languages, then select the dictionary you want to use.


Removing a word you have accidentally added

  1. Open your profile folder:

    Click the menu button New Fx Menu , click help Help-29 and select Troubleshooting Information. The Troubleshooting Information tab will open.

  2. Under the Application Basics section, click on Show FolderOpen FolderShow in FinderOpen Directory. A window with your profile filesfolder will open.
  3. Note: If you are unable to open or use Firefox, follow the instructions in Finding your profile without opening Firefox.

  4. Click the menu button New Fx Menu and then click ExitQuit Close 29 .
  5. Open the file persdict.dat in a text editor (such as WordPad) (such as Pages) (such as Calligra Words).
  6. In the text editor each word you've added is on a separate line. Remove the line, containing the word you wish to remove.
  7. Click the File menu, and select Save, to save your work.
Note: Removed words apply to all your dictionaries.

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